Steam electric iron



May 13, 1952 R. HEDENKAMP 2,596,684

' STEAM ELECTRIC IRON Filed Dec. 3, 1945 2 SHEETS-SHEET 1 i; HEI;

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ao 82 66 yg: 2

alf 6s g l as 62 ,2 E

/lf 5'/ 5l /o k l w INVENTOR May 13, 1952 R. l.. HEDENKAMP STEAMELECTRICl IRON 2 SHEETS-SHEET 2 Filed DeC. 5, 1945 WKN Patented May 13,1952 UNITED ENT 7Gil? FICE .2,596,684 i sTEMELEcT-RICYIRON Richard- L.HedenkampfKirkwood, M0.

:Application December s, 1945, s-eriarNogcszAss 11 This inventionrelates in;generalrtosamrons of the electricalresistance-heated'typefandhas particular reference-to improvementsinsadirons of this character, `including `improvecli-'facilitiesadapting the same forso=calld^steam-pressing An object of theinvention^fis*torprovidaa greatly simplified and. fullyeftective'*steam-electric iron for. domesticuse" or use'inj' commercial pressingestablishments 'and the likeff which"A is fully capable ofemploymenteitheras'zian-independent steam-'electric '.iron,"as'ahot"iron"without the steaming provision,"or as a:"steam=electriciron in connection'with a. constant"s upply of water to permitcontinuous useof"thefiron'for any extended period' as may be desired.

Another object is to provide S an W'improved steam-electric ironofanovel and relativelyfsimpliled construction,v in which are embodied`effective steam generating and steam `deliverypro vision andautomaticmeans "inic'ontrolofsaid provisions,V the' vlatterinc11`1'ding'n1`eans` aorcling facultative regulation l'of'steam-delivery in pressing.

A further object is to, provide vin ariin'iproved ironfof 'the characterindicated; ast'eam generating provision which is effective for 'steamjgeneration onlyw when the iron islin al. pressing position, andexcessive" pressure r'elieving l' provisions' including athermostatically "controlled [pressure relief valve in operativeassociationwith". the steam generator.

OtherA objectsV andv advantages of the-'present improvements will appearreadily from the'A following description of a presentlypreferredembodiment of the invention asmexemplifiedrby the accompanyingdrawings, wherein:

Figure 1 is a sectionalelevation ofl the-lm proved iron, as takenlongitudinally therethrough;

Figure 2 is an enlargedsectional view-"ofthe steam valveassemblyllofthe'- steaml generating means;

Figure 3 is a fragmentary` plan view-off'the sole plate of the iron;

Figure 4 is a longitudinal vsection through-fthe 45 sole plate, asviewed from lined-4in Figure-- 3;

Figure 5 is a fragmentary plan view ofthe-sole backing plate;

Figure 6 is a longitudinalsection throughz.,.the backing plate, asviewed fromzlinefS--B-in Figure 5;

Figure 7 is a fragmentary'planviewof azgasket plate utilized withthefsole andfbackingvplates, and

lFigure 8 isa longitudinal section-throughwthe ..2 gasket/plate; asviewed lfrom .line-f 8-"8 in` Figlure?.

Referring to the -drawingand rst to Figure 1,fthe vpresently-'improvediron includes-a pressingor sole-'plate 510, a backing plate IIS-ofribbed construction (Fig. 5), superimposed onthesole plate; anelectrical heating resistance unit I2' of plate-like form,interposedbetween the sole and -ba'cking plates, ancla gasket plate I4between the l0-unit I2 and the inner surface of the sole-plate.

Thesepartsare secured in assembly by any suit- 1 able Ymeans, such-asthe vstudv bolt I5, andby present preference, additionally by the Valvecasing YI of the main steam control valve' pres- .il ently to bedescribed. Overlying theV plate assemblyabovedescribed, is a casing orhood mem- ;ber; 4S which may besuitably removably vsecured to theplatestructure in any well known man- "ner, or by`-means preferred andvpresently tobe 20 "described, and vexternally on the hood in'av hol-)lowhandle' I9. 'An'ielectric cable 20 for supplying'the resistance unitI2 `with heating' current, is.A extended through a handle. opening 22Vpreferably at the rearfend'of" the handle, and thence 25` through thehandlev tov .a` connection of one -lead l,23. tdtheheatinglunit I2, andthe opposite vlead V2li to onejterminal 28 of a suitable thermostaticheat regulatoindevicel 2],Uthe construction and i. operation of which iswe1lknown. The device 21 -j-30flocatedfin -the forwardend of the hoodI8;-and f suitably Inounted'upon the-backing plate II,1has itsfoppositeterminal 2,8connectedto the heating tunit-'IZwby alead-BU. Regulationofthe thermoo fzsstatic .controlfdevice .to determine the degreeof"UDf-ironfheatingisf presently effected by a rotary finger-tipawheelfgelement 3 I secured; uponl the :thermostat: control-shaft 32 andexposed through the? forwardfside ofilthefhandlef I9. -By presentxpr'eference,thewheel 3 I Lhas'an' ofPf position in lwhichsfthefconductor' circuitto 'the hea-ter unit I2 "is open-'circuitedithroughthedevice 21.

' The hood I Y -which Visf-formed `from' a lsuitable rrust-resistantmetallic sheet material, i supports i i interiorly thereofa wall'memberlloflike rust- 'resistantA material, thewallpreferablybeing suitab1y"secured 'alongf'its margins to'. the hood andlformingiwith the-latter, `a v'chamber' or water 2'reservoir'35.Aninternallythreaded port 36 nor- `r50.mallyclosed by ia' threaded plugV'38, is provided in "the top of! thelhood,^forfthe..admissionordischarge of water relative to the .reservoir ."35. Longitudinallyspacedbaiile plates 43 9 having. ports l 40 therethrough Y. extend.transversely fof fthe 55.-. chamber andserve to dampen reciprocatorymotion of the body of water in the reservoir dur communicating juncture48 inwardly of the forward tip end 50 of the sole plate, and extendingcentrally -longitudinally of the plate from the juncture 48, is a supplychannel5l. The channel 5I from its end somewhat centrally of the soleplate surface 42, is continued through opposite preferably curved branchsupply channels 52, into communication with the side channels 43 Yasillustrated in Figure 3. Steam delivery to the pressing face or surface54 of the sole plate is afforded from each of the side channels 43through-a series of passages 55 through the plate, each passageterminating in an outwardly flaring or conical port 56 opening to theplate surface 54. From the passage 55 at the juncture 48, the passagesin each channel 43 are increasingly relatively spaced along the channelas shown in Fig. 3, in order to provide efficient distribution of steamto the fabric under press beneath the sole plate. Moreover, thearrangement of the supply and delivery channels and passages in the soleplate is such as will least affect uniform heat distribution throughoutthe sole plate.

Steam generation in the channels 43, 5I and 52 is facilitated by theclose adjacence thereof to the resistance heat unit I2 overlying thesame. However, in order to prevent direct contact of steam and watervapor with the unit I2, a relatively thin plate gasket I4 (Figs. 7 and8) heretofore referred to, formed of a non-corrosive metallic material,is interposed between the heating unit I2 and the sole plate and formsthe top closure for the several channels. The gasket platefurther ischaracterized by'high heat conductivity, and Vhence serves to conductheat to the channels for steam generation therein.

Water supply to the steam generator channels is effected from thereservoir 35 through the valve casing I6 (heretofore mentioned) of acontrol valve device 58 (Figs. 1 and 2). Valve casing I6 is externallythreaded at 59 over its lower section,

- for threaded reception in a threaded opening 60 ceive both the valvecasing and the flange 64 of the gasket opening 62. An assembly nut 66 onthe threaded valve casing, serves to lock the valve casing to the soleplate by clamping engagement with the backing plate I I, andadditionally aids the stud bolt I5 in holding the sole plate, backingplate, gasket and heater unit in clamped assembly. The upper portion ofvalve casing I6 is formed to provide an annular flange seat 61v and acentral upstanding, neck 68, the latter projecting inwardly of thereservoir 35 (Fig. l) through an opening 10 in the reservoir wall 34.The wall marginal portion 1I vdefining the opening 18. is seated on thecasing seat 61 and is 4 firmly clamped thereon by a nut 12 threaded ontothe neck 68. It is to be noted here that the nut 12 in clamping the wallmargin 1I to the casing seat 61, affords a ready means for removablymounting the hood IB and the reservoir to the pressing plate assembly.

The casing neck 68 is axially bored to provide a frusto-conical valveseat 14 therein, for cooperation with a control valve 15. Extendingradially through the neck 68 and opening in the valve seat 14, are waterdelivery passages 16, these communicating through radial passages 18 inthe nut 12, with the reservoir chamber 35. Opening to the valve seat 14axially thereof, is a neck passage 19 which is outwardly enlarged oriiared at its lower end to provide a valve seat for a ball check valve82 of a predetermined weight, arranged in the longitudinal chamber 83 ofthe valve casing. A pin or stop element 84 projected transverselyV ofthe chamber 83 below the ball 82,r retains the ball valve in -operativerelation to its seat and limits opening displacement of the ball valve.Nearv the lower end of casing chamber 83 are diametrically oppositepassages 86 through the casing I6, these passages being provided tocommunicate chamber 33 with the central channel 5I in the sole plate I0.

Control valve 'I5 is carried by or formed on the lower end of a valvestem 81 which extends upwardly through reservoir 35 and terminates in athreaded head 88 vthreadedly received through a nut 90 secured to thehood I8 as shown in Fig. l. The upper exposed end of the head 88 hassuitably attached thereto, a control handle or finger-tip control knob9|V through which the valve stem 81 may be rotated for adjustablyrelating the valve 15 to its seat 14. Since the nut 90 is fixed,rotation of the threaded head 88 therein serves to displace vthe valvestem and valve upwardly or downwardly according to the direction of headrotation, so as to determine correspondingly, a lesser or greaterrestriction by the valve 15 to iiow communication between the valve seatpassages 'I6 and 19.

Near the upper end of the forward wall portion 92 of the chamber 35 andabove the normal level of water in the reservoir when the latter isfilled, is a vent port 94 which is controlled by a valve element 95externally of the chamber on the end of a thermostatic member 96 fixedat its lower end to the wall portion 92 (Fig. 1). The purpose andfunction of this valve controlled vent 94 will appear presently.

In normal operation with a suitable .volume of water in the reservoir 35and the iron electrically heated to the desired temperature ascontrolled by the device 21 regulated through the wheel 3l, adjustmentof the valve 15 to an open position as effected through the fingertipcontrol 9I,permits a correspondingly regulated iiow of water from thereservoir 35 through valve passages 18, 16 and 19, past the ball checkvalve 82 and into the valve casing chamber 83. The interior of chamber83 is heatedv from the heater unit I2 by heat conduction through` thegasket plate flange 64 in close surface contact with the valve casingI6, and thence through the valve casing I6, so that the wateradmitted'to the chamber 83 becomes heated and tends quickly tor vaporizetherein. The water vapor'V thus formed then passes through chamberpassages 86 into and along the sole plate channels 5I and 52 to the sidechannels 43. In these channelsD the water vapor is transformed by highheat conduction from the heater unit I2 Ythrough the gasket plate.la-intesteamr and -asthefsteamas .so generated, it issues* throught3the -s'ole 'plate ports" .56 tothe pressingsurface:- ofthe Jiron jforsteaming and moistening the'fabrieunder press.

" -Normally the.; ball check valve* '8 2' will remain open; but intheteve'nt' of=an'undesirableior-"inordinate risel in steam or'vapor1`pressure `in. the casingfchamber 83;' the-'ball valve Will-respond byupward displacement toclose 'the-passageL 19 for preventing ysteam -orvapor flow into Y'the reservoir 35. NWhen' suchpressure-isrelieved'through'the sole plate ports 56, the ball checkwillreturn vto lits openv position for continued. steaming'foperation ofthe iron.

' While 4the wvater supplyv'alve "l 15 normally regulatesl the rate `fofwater *delivery-from the reservoir :1:0- the steamgenerator; it alsovserves as a safety'release device-in"the-eventl the valve and there'isavolumefofrvvater'fin'the-reservoir.

-If under these conditionsf-the-iron ish-employed for any appreciableperiod; the 'indirect heating 'of the vreservoir water;as'throughiheatconduc- Vtion thereto through` the valvecasing- I6andiwall 3ft-will produce eventually a considerable vapor pressure inthe reservoir, tending-'if'prolonged, vto'reach a dangerously-highvalueif not relieved.

Accordingly, the present'improvements affording the support of the valve15Y`directly'onthe yhood 18 (Fig. l), thusenables relief of excessivevapor pressure in the reservoir, since the vapor pressure passages.

-will afford suicientpressure fordeliveryofwater through thecontrolvalve to the steam'generator However/in the event of; inordinateheating of the water flow vvalve' Ain* the region of the valve seat -1Il, such Vas to lproduce vaporization of the water in such zone, Whichifpermitted to continue would prevent-'water lldelivery *to the steamgeneratorpassages, vthe resulting vtemperature of the water-in thereservoir 'andconsequent heating of the wall portion 92 `to-vvhich thethermostat 96 -is` securedywill-cause`fthe thermostat to movevalve195;into'vaposition-of vent closure at the vent -port#94.Consequently, the vapor pressure will-'rise'1inf-thereservoirl-35 to a'point which will"assure'positive'bpressure flow ofwater and vaporpast'the 'ow controlr valve to the steam generator passages. f Moreover,should `the pressurelbuild-iup" in `thereservoir proceed morerapidlyth'an it cani be `rel-ieved'l through the open ow controlvalve,"the"ver`1t valve 95'wi11 respond to pressure approachingvdangerous limits, by opening -thevent SlltoI allovrescape of vaporbeneath thefvhodl I8 and eventually to be appreciated ythat by`reason:tl-iereof,` waterl atmosphere, thus-relieving the'pressure in thereservoir.

v-By locating the "loW' controlvalve 1d-"I5 near the forward end'ofthereservoir 35;-and`by forming the -reservoir such* @that fits* length--is many -times the maximum depth;v thereof .f aslbyA a ratio of theorder of 3 or 4 to 1 forexample,fit"will delivery-to thesteamfgeneratormay occurfonly when the iron is in asubstantiallyfhorizontalior pressingw position. 'Tilting theiron"rearwardly 'so that it restsupontheA rearl ends of --the hood -l 8 andsoleplate l0, or upon' the'rear ends of the "hood I8 and-handle 19, willbring'the-waterfllevel *in the -reservoir)-bel0w the seat lll-of thecontrol Thus-by tilting the iron between-pressing operations,y 'theperiod' of pressing service with 'f each -fllling of' the reservoir.'may* lee-materially increased.

'1 When it isldesiredto operate the iron merely as a' --hotiron,-without 'the steaming' provision,

the `reservoir-'may -be lemptied'-oflwaterthrough the filling' -opening36. -Moreover, 'the-l present i assembly-iis such as'to facilitatecomplete Edrain- -age of vthe reservoir, valve passages and steamingYpassages in fthesole plate `IIL-"when the ironis to be stored for anyextended'perid'this being accomplished byremoving the hood lthrouglrremoval v of theassembly'V nut 12. Then the reservoir VWater may' be`dischargedithrough either or both the opening 10 and the'lling opening.36,

ywhile the valvepassages and steampassages may vbe equallyreadilyemptied` of all. moisture. The

nut'12 can be vremoved by rst rotating the valve stem 81 out'ofengagementwith nut 90,-- then rotating nutemlfout of engagement with`hood I8, and finally inserting a tool through the-opening normallyoccupied by nut 90 andturning nut 12.

A further feature of the presentrimprovements Y.concerns the readyadaptation of the iron for continuous steaming :operation in .instanceswhere pressingis to be conducted'orlong periods at a time, as f occursin commercial pressing establishments for' example. The threaded fillingopening- 36` isselected such thateit is suitable to receive one end ofla' flexible; pipe or -hose '(not shown) leading from a constant sourceof water, as'the house water systermso as .to provide a constant supply.of` water in the reservoir 35. The same result may be obtained indomestic use where it isdesired, through alike hose connection as toawater tapor-'thelike 'From the foregoing, it lvvill4 now appear thatthere is aiforded by the present improvements,l an electric-steam Aironhaving al1 ofthe advantages hereinbefore--enumerated and' others nowapparentfandwhich is of greatly-simplified and economical constructionand fullyautomatic in its operation. While buta single preferredembodiment ofthe iron isvv herein-shown` andA described, nevertheless,it is to be `understood that alterations and modifications of the partsand their arrangement, may bemade Without departing `from the spirit andfull intended scope of the inventionf as defined by the appended claims.

What I claim is:

l. In a sadiron, a pressing plate, saidpressing plate having openingstherein for-outlet of iluid, a heatingA element in heat-transferringrelation with said pressing platef afluid reservoir spaced from saidpressing plate, a valve seat at the bottom of said fluid reservoir, apassage from said valve seat to the openings in saidpressing plate, anda valve stern that is adjustably supported by the top of said uid'reservoir andv is in register with said valve seat, said valve stemrbeing supporated by a portion ofsaid reservo-ir and being movablerelative to said Vportion of said reservoir to move'toward and awayfrom'said valveseat, said'fluidv reservoir being deformable by excessiveV'pressure to move saidrp'ortion' thereof AandJ-said valvestem awayfromrsaidrvalveseat 'tovent-said pressing plate.

2. In a sadiron, a pressing plate, said pressing plate having openingstherein for outlet of fluid, a heating element in heat-transferringrelation to said pressing plate, a fluid reservoir spaced above saidpressing plate, a valve that controls flow of fluid from said fluidreservoir to said openings in said pressing plate, a vent in a wall ofsaid fluid reservoir and a thermally responsive element that is normallyspaced from said Vent but is a-ctuable by heat to close said-vent, saidvent normally being open to permit gravityinduced flow of fluid fromsaid fluid reservoir t said openings in said pressing plate, said ventbeing closable by said thermally responsive element to permit thegeneration of a pressure in said fluid reservoir that will induce flowof fluid from said fluid reservoir to said openings in said pressingplate, said thermally responsive element being of resilient material,said thermally responsive element being deformable in response toexcessive pressure in said fluid reservoir to open said vent even whensaid element is heated.

3. A sadiron that comprises a pressing plate, said pressing plate havingopenings therein for outlet of steam, a fluid reservoir, an outlet forsaid fluid reservoir, a'passage between said outlet for said fluidreservoir and said openings in said pressing plate to conduct fluid fromsaid uid reservoir to said openings, a manually-operated valve thatregulates the flow of fluid through said passage from said fluidreservoir to said openings in said pressing plate, a pressure-responsivevalve element that is positioned between the outlet of said fluidreservoir and said openings in said pressing plate, and a valveseat thatis intermediate said outlet of said fluid reservoir and said openings insaid pressing plate, said valve element being movable by the pressure ofsteam adjacent said openings toward said valve seat to prevent flow ofsteam from said pressing plate into said fluid reservoir. l

4. A sadiron `that comprises a pressing plate,

said pressing plate having openings therein for outlet of steam, a fluidreservoir, an outlet for said fluid reservoir, a passage between saidoutlet for said fluid reservoir and said openings in said pressing plateto conduct fluid from said fluid reservoir to said openings, amanually-operated valve that regulates the flow of fluid from said uidreservoir to said openings in said pressing plate, a pressure-responsivevalve element that is positioned between the outlet of said fluidreservoir and said openings in said pressing plate, and a valve seatthat is intermediate said outlet of said fluid reservoir and saidopenings in said pressing plate, said valve element being movable by thepressure of steam adjacent said openings toward said valve seat toprevent flow of steam from said pressing plate into said fluidreservoir, said pressure-responsive valve being positioned between saidmanually operated valve and said openings in said pressing plate andbeing normally open.

5. A sadiron comprising a pressing plate, said pressing plate havingopenings therein for outlet of steam, a fluid reservoir, an outlet forsaid fluid reservoir, a passage between said outlet for said fluidreservoir and said openings in said pressing plate to conduct fluid fromsaid fluid reservoir to said openings, a manually-operated valve thatregulates flow of fluid through said passage from said fluid reservoirto the openings in said pressing plate, and a pressure responsive valveelement and seat between said manually-operated valve and said openingsin said pressing plate, said pressure-responsive valve normally in openposition to permit flow of fluid from said fluid reservoir to saidopenings in the pressing plate but being closable against said seat inresponse to the pressure of the steam in said openings in said pressingplate to prevent flow of fluid from said fluid reservoir to saidopenings on said pressing plate and toprevent flow of steam from saidopenings in said pressing plate into said fluid reservoir.

6. A sadiron that comprises a pressing plate. said pressing plate havingopenings therein for outlet of steam, a heating element inheat-transferring relation with said pressing plate, a fluid reservoir,an.outlet from said fluid reservoir, a passage between said outlet forsaid fluid reservoir and said openings in said pressing plate to conductfluid from said fluid reservoir to said openings, and apressure-responsive valve that is positioned between the outlet of saidfluid reservoir and the openings in said pressing plate and is openableto permit passage of fluid to the pressing plate and is closable toisolate said fluid from the fluid reservoir so it can generateconsiderable pressure, said valve being normally open but being closableby the pressure of steam in said openings in said pressing plate.

7. A sadiron that comprises a pressing plate, said pressing plate havingopenings therein for outlet of fluid, a heating element inheat-transferring relation to said pressing plate, a fluid reservoir, avent in a Wall of said reservoir, a resilient closure for said vent, avalve seat at the bottom of said fluid reservoir, and a valve stem thatis adjustably supported by another Wall of said fluid reservoir and isin register with said valve seat, and said valve stem being adjustablerelative to said other Wall of said reservoir to move toward or awayfrom said valve seat and thereby stopor pass liquid to said openings insaid pressing plate, said resilient closure being deformable to permitopening of said vent when the pressure in said fluid reservoir becomesexcessive, said reservoir being deformable to move said other wall ofsaid reservoir and the valve stem supported thereby away from said valveseat when the pressure in said fluid reservoir becomes excessive.

8. A sadiron that comprises a pressing plate, said pressing plate havingopenings therein for outlet of fluid, a heating element inheat-transferring relation to said pressing plate, a fluid reservoir, avent in-a wall of said reservoir, a

resilient closure for said vent, a valve seat at the move toward or awayfrom said valve seat and thereby stop or pass liquid to said openings insaid pressing plate, said resilient closure being deformable to permitopening of said vent when the pressure in said fluid reservoir becomesexcessive, said reservoir being deformable -to move saidother wall ofsaid reservoir and the valve stem supported thereby away from said valveseat when the pressure in said fluid reservoir becomes excessive, saidAresilient closure being thermally responsive to the temperature of saidfluid reservoir to opensaid vent when the fluid in said fluidreservoiris cool. ,j v v-9,. Ina sadiron of; the character described, a

pressing plate assembly including an electric heater element, saidassembly providing steaming passages therein opening to the pressingsurface of the assembly, a hood arranged over` said assembly and formedto provide a deformable uid reservoir therein, a member :arrangedbetween said assembly and reservoir and formed to provide passage meanscommunicating the reservoir with said steaming passages, a valveseatpast which fluid flowing through said passage means must flow, and avalve element, said valve element being movable against said valve seatto prevent iiow of iiuid through said passage means and being movableaway from said valve seat to permit flow of uid through said passagemeans, said valve element being supported by a wall of said fluidreservoir and being adjustable relative to said wall to move against andaway from said valve seat, said wall of said uid reservoir being movableupon deformation of said iiuid reservoir to carry said valve elementaway from said valve seat, said uid reservoir deforming upon thegeneration of excessive pressures therein, thereby moving said valveelement away from said valve seat and permitting :duid to ow throughsaid passage means and vent said pressure.

10. In a sadiron of the character described, a pressing plate assemblyincluding an electric heater element, said assembly providing steamingpassages therein opening to the pressing surface of the assembly, a hoodarranged over said assembly and formed to provide a deformable fluidreservoir therein, a member arranged between said assembly and reservoirand formed to provide passage means communicating the reservoir withsaid steaming passages, said member being secured :to one wall of saidreservoir, a valve seat on said member that communicates with saidpassage means, and a valve element that is movable toward and away fromsaid valve seat to prevent or permit flow of uid through said passagemeans, said valve element being supported by that wall of said fluidreservoir which is opposite to said one wall and being movable relativeto said second Wall to move toward and away from said valve seat, saidsecond wall being adapted to move said valve element away from saidvalve seat Iwhenever pressures Within said fluid reservoir deform saidfluid reservoir, said fluid reservoir being stiff and normally beingcapable of maintaining any predetermined setting of said valve elementrelative to said valve seat.

11. In a sadiron of the character described, a pressing plate assemblyincluding a heater element, said assembly providing steam passagestherein opening to the pressing surface of the assembly, a uid reservoirarranged over said assembly, a valve seat and a valve element that areseparable to permit flow of fluid from said fluid reservoir to saidsteam passages and are engagable to prevent flow of uid from said fluidreservoir to said steam passages, a vent in one wall of said uidreservo-ir to vent pressures created within said iiuid reservoir, and athermally-responsive element positioned adjacent said vent, saidthermally-responsive element normally being spaced from said vent topermit ready venting of pressures within said fluid reservoir butresponding to heat to move toward and close said vent, saidthermally-responsive element being of resilient material, said thermallyresponsive element responding to excessive pressures within said fluidreservoir to move away from and open said vent but being again movabletoward said vent whenever said pressures have been vented.

RICHARD L. HEDENKAMP.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,548,957 ,Slobotkin Aug. 11,1925 1,681,911 Spencer Aug. 21, 1928 2,178,512 Schreyer Oct. 31, 19392,188,011 Miller Jan. 23, 1940 2,309,427 Wolcott Jan. 26, 1943 2,313,382Kistner Mar. 9, 1943 2,316,907 Wallace Apr. 20, 1943 2,322,593Riddington et al. June 22, 1943 2,337,078 Morto-n Dec. 21, 1943 FOREIGNPATENTS Number Country Date 330,870 Great Britain June 19, 1930

